rover 3.5v8 charged

[series3-2007]

hey guys, i've been pointed in your direction by a member of landrover net forum, me and a friend have recently rebuilt a 3.9v8 (out of a rangerover classic), i've also been informed that the 3.9 has had trouble in the past with poping head gasgets,

i do have a spare SD1 3.5, and to make some radical a supercharged 3.5 , but turbos & superchargers and completely new to me, where do i start lol??

cheers mark

[bones]

i run a 3.9 with 125 of nos and ive had no problems yet with head gaskets, (or have i spoke to soon ). If your after turbos let us know as ive got 2 to get rid off rich

[CastleMGBV8]

Mark,

Welcome to the forum.

Assuming the vehicle is a Land Rover, what usage is intended and what sort of power delivery sre you looking for?

The 3.9 engine is just a larger bore version of the late stiff block 3.5 engine and as such is no more prone to problems in respect of head to block sealing.

A gasket can only work well if the two mating faces are perfectly flat and the early type tin gaskets will be ok for most road modified engines, the later composite head gaskets are thicker an have better sealing potential especially if the mating surfaces are not 100% flat.

If you want a high torque engine then the 3.9 would be a better place to start from, if the engine is in good condition with good cylinder sealing, I suggest a compression and leak down test before doing any mods, then you could fit a blower type cam and new lifters, the composite gaskets which will lower the compression ratio by approx .5/1 (assuming you have a 9.35/1 engine to start with) and then fit a low pressure blower capable of providing say 6-8psi of boost from off idle, this will give you all the bottom end power you probably need.

It would be a good idea to fit an ARP mains stud kit to add stability to the mains caps but if you are not going to use a lot of revs this may not be necessary but I would do it for peace of mind.

As to the type of blower, there are others on the forum better qualified to offer advice.

Might be a good idea to buy a copy of Des Hamills book "How to Power Tune Rover V8 engines" not cheap but it could save you making costly mistakes.

Kevin.

[kiwicar]

As Kevin says, what are you looking for out of the engine, is this a comp safari type set up or a rock crawler/ green laner mud monster? also are you going manual or auto box? sorry alot of questions.
I certainly do as Kevin says and start with the 3.9 block, ARP studs would be a good thing if you are going to up the power above about 250bhp, appart from that the rest is down to what you want to do with it.
Best regards
Mike

[topcatcustom]

Rich- I have a 302 that might start begging me for TT's are they the right size?

[kiwicar]

Now you are talking Tom. . . turbos on a 302, good pair of heads nice cam bottom end brace. . . 750- 900 bhp gosh I am getting interested already.
Best regards
Mike

[series3-2007]

hey, thanks for the warm welcome, yeah the basis is a rangerover chassis, with a mix of alu and steel landrover panels, at the moment it's a a got 5 speed defender box with the 3.9, i've got the 3.5v8 spare, as a replacment if anything happens, ,

Kevin:

this is most definately a green laner, mud monster , once the charger has been fitted, i'll be reverting from a manual 5 speed to a rangerover 4 speed auto box, i've been informed this should take the power with ease,

[SuperV8]

How good are you electronics?

If you go supercharger route, i'd say go the roots type blower is the one to go for for (lots of old jag ones on e-bay) better low end torque but it's best to use engine management to control it. Twin screw type would be the best but expensive.

Or you could find a cheap 4.6 for low end grunt and hope it hasn't got leaky liners but simpler than a supercharger, just a bolt in fit.

Tom.

[kiwicar]

Hi
for a green laner I would go 4 speed auto, personally a 4.2 not a 4.6, but that is because I think there is a fundemental problem with the design of the 4.6, a twin screw (sprintex) style supercharger through a nice big intercooler run about 8 to 10 psi boost on 8.5 to 8.75 cr with the best heads you can a afford. I recon Buick 300s and flat top pistons (the ones Ian stewart found for the ford mod engine) would be the best combination here especially if you skim the heads to improve the squish band, even better weld them up a bit to improve the squish band further. Megasquirt it and away you go. A roots type blower off a jag would be a cheeper solution and nearly as good but in that case most definatly intercool it. Choosing the right cam could be interesting, but the one from real steel for a blower motor would be a good start. Oh and nice tube headers, long 4 into 1s at 1.5" od into an x pipe. sounds fun to me.
Best regards
Mike

[topcatcustom]

Mike I love reading your cheap and equally as realistic suggestions

If I had no job and lots of money I'd most definately follow your orders!!!

[kiwicar]

Hi Tom
Now come on, it wasn't me who mentioned turbos on a 302, all I was doing was taking it along to its logical conclusion!
As for buick 300 heads they are about £350-350 a set in good condition and can be rebuilt for sensible money using chevy valves, retainers and springs etc and rover rocker gear, they flow really well as is so they don't need fancy porting work and their only limmitation normally is that they are a large chamber at 54cc, leading to low CR. here it is a posotive asset as lower CR is what this chap wants and he can use flat top pistons that should help with the not so brilliant rover/buick chamber design.
I'm off to lick my wounds now
Best regards
Mike

[Coops]

watch him tom,
once he gets in your head you have had it,

i should know

[kiwicar]

You are all so cruel!

So Tony now you've stopped mucking about with the bottom end when are you going to get that supercharger fitted???

Best regards
Mike

[Coops]

funny you should say that

[topcatcustom]